Air pump capable of pumping air quickly

ABSTRACT

An air pump is disclosed to include a plurality of pumping units. Each pumping unit has an air cylinder and a piston rod adapted to be reciprocated in the air cylinder to pump air. A rotating device is adapted to reciprocate the piston rods of the pumping units at the same time when rotated. And a driving device is provided at a side of the rotating device and adapted to rotate the rotating device.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates generally to air pumps and, more particularly, to such an air pump that has multiple pumping units capable of pumping air quickly.

[0003] 2. Description of the Related Art

[0004] Conventional air pumps are commonly designed to pump air by reciprocating a piston rod in an air cylinder. The area of the cross section of the piston rod has a great concern with air resistance. Due to the limitation of the cross-sectional area of the piston rod and the air cylinder, the pumping speed is limited. In order to enhance the pumping effect, air pumps with multiple air cylinders are developed. However, these multi-cylinder air pumps are still not satisfactory in function because they have only one pumping unit in action when operated.

SUMMARY OF THE INVENTION

[0005] The present invention has been accomplished under the circumstances in view. It is one object of the present invention to provide an air pump, which simultaneously drives multiple pumping units to pump air when started.

[0006] It is another object of the present invention to provide an air pump, which uses a rotating device to reciprocate the piston rods of multiple pumping units to pump air at the same time.

[0007] To achieve these objects of the present invention, the air pump comprises a plurality of pumping units. Each pumping unit has an air cylinder and a piston rod adapted to be reciprocated in the air cylinder to pump air. A rotating device is adapted to reciprocate the piston rods of the pumping units at the same time when rotated. And, a driving device is provided at one side of the rotating device and adapted to rotate the rotating device.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008]FIG. 1 is a perspective view of an air pump according to the present invention.

[0009]FIG. 2 is a side view of the air pump according to the present invention.

[0010]FIG. 3 is a sectional view taken along line 3-3 of FIG. 1.

[0011]FIG. 4 is a schematic drawing showing air forced into the cylinder according to the present invention.

[0012]FIG. 5 is a schematic drawing showing the check plate moved away from the air inlet according to the present invention.

[0013]FIG. 6 is a schematic drawing showing the check plate stopped at the air inlet according to the present invention.

[0014]FIG. 7 is a perspective view of a flat valve body for the air pump according to the present invention.

[0015]FIG. 8 is a schematic drawing showing an alternate form of the pumping unit according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0016] Referring to FIGS. 1˜7, an air pump in accordance with the present invention is shown comprised of a casing 10, at least one, for example, three pumping units 20, a rotating device 30, an air accumulator 50, and a driving unit 60.

[0017] Referring to FIGS. 1˜4, the casing 10 has a bottom locating shell 11 and a top locating shell 12 spaced above the bottom locating shell 11 at a distance. The bottom locating shell 11 has a center axle hole 111. The top locating shell 12 has a center axle hole 121 aimed at the center axle hole 111 of the bottom locating shell 11.

[0018] Referring to FIGS. 1˜4, the pumping units 20 are provided between the bottom locating shell 11 and the top locating shell 12 and equiangularly spaced around the center axle hole 111, each comprised of an air cylinder 21, a piston rod 22, and two axle bearings 23 mounted on the piston rod 22 at different elevations. As illustrated in FIG. 3, the air cylinders 21 of the pumping units 20 are respectively mounted inside the top locating shell 12, each comprising a cylinder body 212, a cylinder cover 211 covering the cylinder body 212, and a seal ring 215 mounted on the cylinder cover 211 and stopped against the inside wall of the cylinder body 212 to seal the gap between the cylinder body 212 and the cylinder cover 211. The piston rod 22 of each pumping unit 20 has a top mounted with a seal ring (or check ring) 221, which is peripherally stopped against the inside wall of the cylinder body 212.

[0019] Referring to FIGS. 3 and 4, the rotating device 30 is provided between the bottom locating shell 11 and the top locating shell 12 and surrounded by the pumping unit 20, having a center shaft 31 mounted in the center axle holes 111 and 121 of the top locating shells 11 and 12. The periphery of the rotating device 30 is shaped like a cam wheel and stopped between the axle bearings 23 of the piston rod 22 of each pumping unit 20. When the rotating device 30 rotated through one turn, the piston rods 22 of the pumping units 20 are respectively reciprocated in the respective air cylinders 21 through at least one cycle. According to this embodiment, the piston rods 22 of the pumping units 20 are respectively reciprocated in the respective air cylinders 21 through one cycle when the rotating device 30 rotated through one turn.

[0020] The cylinder cover 211 of the air cylinder 21 of each pumping unit 20 has an air inlet 24 and an air outlet 25. Air passes from the outside of each pumping unit 20 through the air inlet 24 of the cylinder cover 211 of the air cylinder 21 of each pumping unit 20 into the cylinder body 212 of the air cylinder 21 of each pumping unit 20, and then passes from the inside of the cylinder body 212 of the air cylinder 21 of each pumping unit 20 to the outside of each pumping unit 20 through the air outlet 25 of the cylinder cover 211 of the air cylinder 21 of each pumping unit 20. The air inlet 24 of the air cylinder 21 of each pumping unit 20 is provided with a check valve 26 (see FIGS. 5 and 6). The cylinder cover 211 of the air cylinder 21 of each pumping unit 20 further has a stepped through hole formed of a locating hole 213 of relatively greater diameter at the top and a guide hole 214 of relatively smaller diameter at the bottom. The stepped through hole is disposed in parallel and adjacent to the air inlet 24 of the respective cylinder cover 211. The check valve 26 is comprised of a stem 261 inserted through the guide hole 214, a locating block 213 formed integral with one end of the stem 261 and suspended in the locating hole 213, and a check plate 263 formed integral with the other end of the stem 261 outside the stepped through hole. When air passing through the air inlet 24 into the respective air cylinder 21, the check plate 263 is forced away from the air inlet 24 for enabling air to pass to the inside of the respective air cylinder 21 (see FIG. 5). On the contrary, when air passing out of the air cylinder 21, the check valve 263 is forced by outgoing air to close the air inlet 24, prohibiting outgoing air to pass through the air inlet 24, and therefore outgoing air is constrained to go to the outside of the respective air cylinder 21 through the air outlet 25 (see FIG. 6).

[0021] The air accumulator 50 is located on the top of the top locating shell 12 above the pumping units 20, and adapted to accumulate air passing out of the air outlets 25 of the air cylinders 21 of the pumping units 20 (see FIG. 1). According to this embodiment, the air accumulator 50 comprises an air accumulation chamber 52 formed in the top side of the top locating shell 12 and adapted to collect air from the pumping units 20, and an air nozzle 51 extended from the accumulation chamber 52 for output of air (see FIGS. 3 and 4). Further, a check valve 27 is provided between the air accumulator 50 and the air outlets 25 of the pumping units 20. As illustrated in FIGS. 3, 4, and 7, the check valve 27 comprises a flat valve body 271 fixedly positioned between the air accumulator 50 and the pumping units 20. The flat valve body 271 has three U-shaped valve flaps 272 corresponding to the air outlets 25 of the pumping units 20. When passing out of each air cylinder 21, outgoing air pushes open the U-shaped valve flaps 272 and then passes through the respective air outlets 25 into the air accumulator 50 (see FIG. 3). When air is reversed, the U-shaped valve flaps 272 are forced to close the respective air outlets 25, prohibiting reverse flow of air from the air accumulator 50 into the air cylinders 21 of the pumping units 20 (see FIG. 4).

[0022] The driving unit 60 is adapted to rotate the rotating device 30. According to this embodiment, the driving unit 60 is a motor drive provided at the bottom side of the casing 10 and coupled to the center shaft 31 of the rotating device 30 through a pinion 62, which is fixedly mounted on the output shaft of the motor drive 60, and a transmission gear 61, which is fixedly mounted on the bottom end of the center shaft 31 and meshed with the pinion 62. Further, any of a variety of other driving methods may be employed to drive the rotating device. For example, the output shaft of the motor drive can be directly and coaxially connected to the center shaft of the rotating device; a hand crank may be used and coupled to the center shaft of the rotating device instead of the motor drive; accelerating gear means or reduction gear means may be used and coupled between the center shaft of the rotating device and a motor drive or hand crank.

[0023]FIG. 8 shows an alternate form of the pumping unit according to the present invention. According to this embodiment, the pumping unit 70 is a two-way pumping unit comprised of a piston rod 71 and two air cylinders 72 respectively coupled to the top and bottom ends of the piston rod 71. Each air cylinder 72 is comprised of a cylinder body 722 and a cylinder cover 721. The cylinder cover 721 of the bottom-sided air cylinder 72 has an air outlet 73 connected to a second air accumulator 75, and a check valve 74 mounted in the air outlet 73 to prohibit reverse flow of air. The piston rod 71 has a bottom end mounted with a one-way check ring 76 peripherally stopped against the inside wall of the cylinder body 722 for enabling air to pass from the outside to the inside of the cylinder body 722 through the piston rod 71 and prohibiting reverse flow of air. When rotating the rotating device 77 to reciprocate the piston rod 71 of each pumping unit 70, up stroke as well as down stroke of the piston rod 71 can pump air.

[0024] Although particular embodiments of the invention have been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. For example, linking means may be used and coupled between the rotating device and the piston rods of the pumping units; any of a variety of suitable conventional one-way valve means may be used instead of the aforesaid check valves. Accordingly, the invention is not to be limited except as by the appended claims. 

What is claimed is:
 1. An air pump comprising: a plurality of pumping units each having an air cylinder and a piston provided with a first end inserted into an inside of said air cylinder for reciprocating movement in said cylinder to pump air; a rotating device adapted to reciprocate the piston rods of said pumping units at the same time when rotated; and driving means provided at a side of said rotating device and adapted to rotate said rotating device.
 2. The air pump as claimed in claim 1, wherein said pumping units are spaced around said rotating device; said rotating device has a part coupled to a middle part of the piston rod of each of said pumping units for reciprocating the piston rods of said pumping units through at least one cycle when said rotating device rotated through one turn.
 3. The air pump as claimed in claim 2, wherein the piston rod of each of said pumping units has two axle bearings vertically spaced on the middle part thereof; said rotating device has the part stopped between the axle bearings of the piston rod of each of said pumping units.
 4. The air pump as claimed in claim 1, wherein the air cylinder of each of said pumping units comprises an air inlet, a check valve mounted in said air inlet for enabling air to pass from the outside into the inside of the respective air cylinder and prohibiting air from passing out of the respective air cylinder through said air inlet, and an air outlet for output of air.
 5. The air pump as claimed in claim 4, wherein the air cylinder of each of said pumping units has a stepped through hole formed in one end thereof adjacent to the air inlet and air outlet of the respective air cylinder, said stepped through hole being formed of a top locating hole of relatively greater diameter and a bottom guide hole of relatively smaller diameter; said check valve comprises a stem inserted through the guide hole of the stepped through hole of the respective air cylinder, a locating block formed integral with one end of said stem and suspended in the locating hole of the stepped through hole of the respective air cylinder, and a check plate formed integral with an opposite end of said stem outside the stepped through hole of the respective air cylinder for moving with said stem and said locating block in the stepped through hole of the respective air cylinder to close/open the air inlet of the respective air cylinder, said check plate being forced away from the air inlet of the respective air cylinder when air passing from the outside into the inside of the respective air cylinder, said check plate being forced by air to close the air inlet of the respective air cylinder when air passing out of the respective air cylinder through the air outlet of the respective air cylinder.
 6. The air pump as claimed in claim 5, wherein the air cylinder of each of said pumping units is comprised of a cylinder body and a cylinder cover covering said cylinder body, said cylinder cover defining the air inlet, air outlet, and stepped through hole of the respective air cylinder.
 7. The air pump as claimed in claim 4, further comprising one-way valve means that enables air to pass through the air outlet of the air cylinder of each of said pumping units from the inside of the air cylinder of each of said pumping units to the outside of the air cylinder of each of said pumping units, and prohibits reverse flow of air through the air outlet of the air cylinder of each of said pumping units.
 8. The air pump as claimed in claim 7, further comprising an air accumulator connected to the air outlet of the air cylinder of each of said pumping units through said one-way valve means and adapted to collect air from said pumping units.
 9. The air pump as claimed in claim 8, wherein said pumping units each have one end respectively connected to a top locating shell, said top locating shell being connected to said air accumulator; said one-way valve means comprises a flat valve body fixedly positioned between said air accumulator and said top locating shell, said flat valve body having a plurality of U-shaped valve flaps corresponding to the air outlets of the air cylinders of said pumping units and adapted to close/open the air outlets of the air cylinders of said pumping units to limit the flowing of air to the direction from the inside of the air cylinders of said pumping units to the outside of the air cylinders of said pumping units through the air outlets of the air cylinders of said pumping units.
 10. The air pump as claimed in claim 9, wherein said air accumulator comprises an air accumulation chamber defined in said top locating shell, and an air nozzle extended from said air accumulation chamber for output of accumulated air.
 11. The air pump as claimed in claim 10, wherein said air pumping units each have a second end respectively connected to a bottom locating shell and a casing at a bottom side of said bottom locating shell; said rotating device is coupled between said top locating shell and said bottom locating shell and surrounded by said pumping units; said driving means is provided at one side of said casing and coupled to said rotating device for driving said rotating device to reciprocate the piston rods of said pumping units through at least one cycle when said rotating device rotated through one turn.
 12. The air pump as claimed in claim 1, wherein the piston rod of the air cylinder of each of said pumping units is mounted with a seal ring peripherally stopped against the peripheral wall of the respective air cylinder.
 13. The air pump as claimed in claim 1, wherein said driving means comprises a motor.
 14. The air pump as claimed in claim 1, wherein said driving means further comprises a gear transmission mechanism coupled between said motor and said rotating device.
 15. The air pump as claimed in claim 1, wherein said driving means comprises a handle coupled to said rotating device for driving by hand to rotate said rotating device.
 16. The air pump as claimed in claim 15, wherein said driving means further comprises a gear transmission mechanism coupled between said handle and said rotating device.
 17. The air pump as claimed in claim 1, wherein said pumping units each further comprise a second air cylinder, and the piston rod of each of said pumping units has a second end inserted into an inside of said second air cylinder for pumping air.
 18. The air pump as claimed in claim 17, wherein said rotating device has a peripheral part coupled to a middle part of the piston rod of each of said pumping units for reciprocating the piston rod of each of said pumping units in the first air cylinder and second air cylinder of the respective pumping unit through at least one cycle when rotated through one turn.
 19. The air pump as claimed in claim 18, wherein the air cylinders at the first and second ends of the piston rods of said pumping units are respectively connected with a top locating shell and a bottom locating shell, said top locating shell and said bottom locating shell each having a center axle hole; said rotating device has two distal ends respectively coupled to the center axle hole of said top locating shell and the center axle hole of said bottom locating shell; said rotating device is surrounded by said pumping units.
 20. The air pump as claimed in claim 19, wherein the piston rod of each of said pumping units has one end mounted with a one-way check ring peripherally stopped against the periphery of the respective second air cylinder for enabling air to pass from the outside to the inside of the respective second air cylinder through the respective piston rod and prohibiting reverse flow of air; the second air cylinder of each of said pumping units has an air outlet for output of air. 